


demons in the dark

by SidewaysClarinet



Series: Writer-Bot Shenanigans [2]
Category: Ao no Exorcist | Blue Exorcist
Genre: Alternate Universe - Canon Divergence, Anime Themes, But hey he's getting possessed by Astaroth so it's fine, Gen, I go with Astarte instead of astaroth btw!, Shiratori is an asshole, Writer-Bot Shenanigans, Yukio is tired and needs a break
Language: English
Status: Completed
Published: 2020-11-26
Updated: 2020-11-26
Packaged: 2021-03-10 07:46:58
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,330
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/27729739
Author URL: https://archiveofourown.org/users/SidewaysClarinet/pseuds/SidewaysClarinet
Summary: Shiratori Reiji is not exactly someone that Yukio wants to be interacting with even on a good day, but after a bad one? Even less. That's fine and all, because Shiratori doesn't like him much either.But when Shiratori finds himself the prey of an eager demon king, cooperating with Yukio may be the only option he has left.
Relationships: Okumura Yukio & Shiratori Reiji
Series: Writer-Bot Shenanigans [2]
Series URL: https://archiveofourown.org/series/2027450
Comments: 5
Kudos: 16





	demons in the dark

**Author's Note:**

> Hi guys! This is another fic created out of Writer-Bot, and one I found myself surprisingly attached to! I love the idea of Shiratori and Astarte (The goddess that Atsaroth, a Christian demon, was based on), so this was super fun to write. That, and Shiratori/Yukio is a crackship I'm weirdly attached to, so I may even continue this some day.

Of all the faces that Yukio wants to see after a long day, Shiratori Reiji is so far down the list that Yukio honestly considers him almost even with Satan himself. 

Rin had never allowed them to even come near each other during all of their middle school years, much less face-to-face, but Yukio knew of him. Oh, did he know of Shiratori. The other boy was the most notorious out of all the nasty little bullies that prowled the grounds of their middle school, and his reputation was enough to cross prefectures. He was a nasty piece of work, and Yukio was perfectly fine having never met him in person.

Until he comes back from his last assignment of the day, tired and ready to start the next long day of university applications and mission reports, and sees a familiar head of white hair hunched over and standing on the doorstep of the old dorms. He and Rin were still staying there after all these years because the area was  _ supposed  _ to be private and secluded, and yet that washed up bully had still managed to find his way here. 

“Can I help you?” Yukio asks aloud, unable to completely wash the distaste from his mouth.

Shiratori’s form jumps, and he whirls around. The first thing Yukio sees is the cluster of coal tars clinging to his clothes, and the second thing is the nervousness in his dark eyes. “You- you’re that Okumura nerd, right?”

What an eloquent greeting.

Yukio hikes his bag further up his shoulder, scowling at the other boy. The gun at his hip is far from necessary, but God, is it tempting. “Okumura Yukio, yes,” he answers evenly, instead.

“Where is your dad?” Shiratori asks, but his eyes are everywhere but Yukio. He seems to be searching the area, looking for something, and it has Yukio tensing just about as much as the mention of Shiro does.

“Shiro passed away three years ago,” he says, a little coldly. “You’re a little too late to give a confession, if that was what you were hoping for.”

Shiratori’s scowl deepens, and almost turns desperate. “Well, he was always on that- on that exorcism shit, right? Are you on that too?”

Yukio scoffs and pulls his keys out of his pocket, turning towards the door. “What, were you messing around with an Ouiji board? I can’t help you with that, Shiratori-san.”

Suddenly, a hand grasps his arm tightly and pulls him back around. Yukio’s eyes widen, and he yanks his arm free, turning an offended glare towards Shiratori.

“Don’t grab me-!”

“Just shut up and listen first, won’t you?” Shiratori snaps. Yukio is almost tempted to just leave the asshole out here, in the cold, but the desperation in Shiratori’s voice and expression makes him stop short. “And don’t laugh!”

“There’s nothing funny about this to me,” Yukio huffs. Even so, he waits for the other boy to continue.

After a second, Shiratori finally does. “...I think I’m bein’ possessed.”

Yukio almost laughs—surely Shiratori is pulling his leg, hoping to get one up on him. It’s a thing he’d definitely do; harass an old bullying victim after three years. Where he expects to see a haughty jeer, he only sees Shiratori’s wide eyes, and the nervous sweat dripping down his hairline. He’s genuinely fearful, and it throws Yukio more than he’d like to admit.

“What makes you say that?” he asks after a beat of silence.

“It’s the same as—shit, you didn’t see that, did you?” Shiratori steps back, runs a frantic hand through his hair. “It’s the same shit as with your brother, I- I’m not controllin’ myself, and there’s this woman, and she- fuck’s sake!”

Yukio can’t make a damn bit of sense from what Shiratori is saying, and reluctantly moves his bag out of the way enough to grab the other boy by the shoulder. “Calm down, Shiratori-san, I can’t understand what you’re saying. What woman?”

“This lady! She’s tall, and has this white hair, and she says her name is As- Astarth?”

“Astarte?” Yukio tries, and at Shiratori’s nod, feels concern spike up. Astarte, the demon king of rot, had been radio silent for years. She hadn’t taken up a new body, hadn’t reincarnated or chosen a side in the holy war. It would be long overdue for her to be taking a new body, but Shiratori? “Are you sure?”   
“Yes, I’m sure!” Shiratori snaps. “She’s been highjacking my body for days, how could I not know?”

“Calm down,” Yukio says again, more on instinct than anything. His mind is already running; he knows that Astarte taking up a body could mean any variety of things. More importantly, it means that she may be taking a side soon, or at least can be persuaded to take one if she hasn’t already. 

It’s this that pushes him to invite Shiratori into the old dorm, even though the thought of having the other boy in his home is enough to have disgusted shivers running up his spine. This is more important, he thinks to himself as he pushes Shiratori to sit down at the kitchen table.

“When did this start?” Yukio asks him, leaning up against the table to peer down at Shiratori.

“Just a few days ago, but it happened before,” Shiratori answers, his knee bouncing anxiously. “Your whackjob dad exorcised her, can you do it again?”

“Not so fast, I might be able to work with this.” Yukio takes another close look at him. There’s the coal tars floating close by, of course, but he can also see a flash of fang when Shiratori speaks, and something bony protruding from his hair. Astarte must still be with him, then. “Can you give her control?”

Shiratori’s head snaps up to look at him, bewildered. “No way! I wanna get rid of her, not let her in!”

“I could convince her to leave, if you let me speak to her,” Yukio says impatiently. He’s more than a little eager to get rid of Shiratori for a few minutes, and he’s sure it shows as much as he tries to hide it. A demon king would be a little more tolerable to handle.

But Shiratori only shakes his head, eyes widening. “Hell no! I’m not letting that crazy bitch back in again, do something else!”

Yukio sighs loudly, but at the same time, he can’t act like he doesn’t understand where Shiratori’s coming from. He’d be scared too, if he were being possessed by some spirit that he didn’t know about and didn’t understand. Shiratori doesn’t even know anything about exorcism—as far as he knows, he’s alone in his fight against an unstoppable demon. Yukio tries to force himself to have some empathy, and loosens the frustrated tension from his shoulders.

“Astarte is a demon king,” he starts, quietly. “They’re children of Satan, and she’s one of the eight of them. They each belong to an aspect, and have an informal rank in terms of strength. She’s about sixth in line; she’s stronger than most demons, but relatively weak in comparison with the greater demon kings. That, and she’s likely attuned to your body now. The chances of her harming you are very, very low.”

That seems to relax some of the anxiety in Shiratori’s expression, though it looks as if it only gets replaced by confusion. “What the fuck are demons?”

“Look, I don’t have time to explain everything to you.” Yukio rubs at the bridge of his nose, closing his eyes for a brief second. “I need to make sure she’s not a threat to anyone else on campus, or to the world as a whole. I need you to trust me and let her take the reins.”

It’s kind of a joke, really. He knows that Shiratori is prideful (and that’s putting it lightly), and Yukio doesn’t expect him to actually follow through on directions. However, to his surprise, Shiratori gives a reluctant little nod. 

He closes his eyes, and as a few seconds of silence pass, there’s a bit of a shift in the room. It feels almost akin to a gear of great size slotting into place, silently and smoothly. Another beat passes, and when Shiratori opens his eyes again, they’re a deep, ruby red.

“Astarte,” Yukio greets. In that moment, he realizes that maybe talking to a demon king alone, with no backup, may not have been the best idea in the world. He prays to God that Astarte won’t start a fight, because he knows damn well that she’ll finish it.

Thankfully, the look she gives him isn’t one of incoming violence. “Human. You’re of True Cross, aren’t you?”

“I am.” He nods, mentally taking stock of the gun at his side. “So I hope I don’t offend when I ask what your intentions are with Shiratori-san.”

“The kid?” Astarte lifts an arm, looking over Shiratori’s form. “He’s a good boy. Real compatible, I’d say. I want to keep him.”

“I could work that out for you, provided you tell me which side of the war you plan to use him for.”

At that, Astarte laughs. “Whichever side lets me out the most often! Give me battles and bloodshed, and I’ll be a happy woman.”

“We could arrange that for you.” Thankfully, her demands are simple. She reminds him quite a bit of Amaimon; all too used to human antics, and more focused with the simpler pleasures of life than the drama of it all. It makes her more predictable, but no less dangerous. “If the blood you draw is on the Order’s behalf, I see no reason why I should have to exorcise you from his body.”

“Well, that works out then, doesn’t it?” Astarte hums, giving him a sharp-fanged grin. “Because I see no reason to leave a body so made for me.”

Yukio says nothing to that. There’s a predatory look in her eyes that he doesn’t want to engage with, much less be around, and it has him eager for the demon king to get bored and leave already.

Astarte’s expression turns unimpressed, and a little put-out.“I’m guessing you’ll be wanting one of those contracts from me, then.”

“We will,” Yukio agrees. “Though, that can wait for tomorrow. If you leave him be for tonight, I’ll have him come back tomorrow and we can work out the finer details with my superiors.”

She doesn’t reply to that, only gives a little huff of a breath before the light in her eyes abruptly goes out. Shiratori’s body topples forward limply, and Yukio’s eyes widen before his brain finally catches up to his body. He leans forward to catch the other boy, and an ‘oof!’ left his lips as he took the brunt of Shiratori’s weight.

Yukio only has a few seconds to scramble to hold Shiratori properly before he suddenly starts wriggling, gripping Yukio’s arms tightly as his eyes finally open.

“Is she gone?” Shiratori asks, desperate.

“Um.” It’s then that Yukio remembers that the other boy had come to him in the hopes of getting rid of Astarte, not making a contract with her. “Well…”

“She’s not gone?!” Shiratori cries. He immediately leaps up, and Yukio yelps as he’s suddenly and rather violently shoved back. “What the fuck! You’re as much of a hack as your dad was, you freak!”

“Hey!” Yukio pushes him right back, scowling. A part of him hisses at him to close the distance, to clock the other boy across the jaw for his words about Shiro, but he stops himself. He closes his eyes, takes a breath, and forces himself to calm down despite the broiling anger. “Listen, I get that you’re frustrated and scared, Shiratori-san, but I can’t help you if you’re going to keep throwing a fit like a  _ child  _ every time I don’t do what you want!”

The end of it has him a bit breathless, and he realizes with a flush of embarrassment that he had ended up losing his temper anyways. He’s not quite humble enough to apologize, but he does sit back down in his chair, and glances away from Shiratori.

“Astarte could be incredibly beneficial to both ourselves and you,” he says, quieter. “If you can learn to cohabitate with her.”

“Cohabitate?” Shiratori repeats, sounding only seconds from blowing up again. “Why the  _ fuck  _ would I do that?”

Yukio clenches his jaw, trying to fight down frustration. It’s entirely too long of a story to tell now, about demons and exorcists and the holy war and all its intricacies, and that wasn’t even counting the story’s rather difficult audience. “I can explain it better if you come back again tomorrow, okay?”

“I’m not goin’ home with that thing!” The other boy snaps.

“What, do you want to stay here, then?” Yukio suggests, irritated. He doesn’t genuinely expect Shiratori to take him up on it, but the following silence speaks volumes. Yukio looks over at him, eyes wide. “You seriously want to stay?”

“Well, what am I supposed to do?” he huffs, looking embarrassed. “What if she takes over while I’m sleepin’? My parents’ll put me in a psych ward!”

Yukio relents, holding a hand up to stop Shiratori’s anxious onslaught. “Fine! Fine, you can spend the night, but if you pick a fight with Rin or anything like that, I’m kicking you out.”

“Deal,” Shiratori agrees, and the speed of it almost surprises Yukio. 

Yukio rolls his eyes but leaves it be, instead pulling his briefcase up from the floor. “Rin and I have rooms on the second floor. You can pick any of them that you’d like. I’ll be down here working, so call me if you need anything.”

“Very homey,” Shiratori grumps. Thankfully, he doesn’t push it, and leaves Yukio alone to go find the staircase.

_ This is going to be a long night,  _ Yukio thinks to himself. He sighs, pulls out his computer, and gets to work.

**Author's Note:**

> Comments and criticisms are always appreciated!


End file.
